Comorbidities Associated With Migraine and Patent Foramen Ovale (CAMP)

The purpose of the study is to compare the rate of comorbidities associated with migraine aura (MA) between persons who have a large circulatory right-to-left shunt (RLS) and those who do not have RLS. Approximately 50% of individuals who have MA also have RLS due to patent foramen ovale (PFO). A PFO is an anatomical opening or flap between the upper chambers of the heart or atria that permits blood to pass from the right of the heart to the left side of the heart, without first going to the lungs to be filtered and oxygenated. Many health conditions and clinical syndromes including stroke, sleep apnea, and migraine have been linked to PFO. Although the mechanism is undetermined, it is hypothesized that microscopic blood clots and chemicals such as serotonin can pass through the PFO, travel to the brain, and cause headache and aura. Persons who have MA are at increased risk for stroke and transient ischemic attacks relative to people who do not have migraine. Migraine is also associated with the presence of white matter lesions in the brain and mild deficits in cognitive function associated with the posterior brain (vision, memory, processing speed). The risk of stroke in migraine is highest for women under the age of 45 who have aura and a high number of migraine headache days per month. No convincing evidence has been produced to explain the mechanism for the increased risk of ischemic stroke in migraine; however, increased platelet activation and aggregation is a plausible theory. We hypothesize that migraineurs with aura and large RLS (presumably due to a PFO) will be more likely to have sleep apnea, increased platelet activation, cognitive deficits, alterations in cerebral vasomotor function, and white matter lesions than migraineurs with aura who do not have PFO. The results of this exploratory study will generate hypotheses as to why subgroups of migraineurs have an increased risk of stroke and the impact of large PFO on comorbid conditions associated with